Properties of the glycolytic pathway: Identify the statement that is NOT true regarding glycolysis in typical cells under standard instructional assumptions.

Introduction / Context: Glycolysis is a central, ancient pathway converting glucose to pyruvate through ten enzyme-catalyzed steps. This item asks you to spot the incorrect statement among commonly taught characteristics.

Given Data / Assumptions:

• Glycolysis occurs in the cytosol and can run anaerobically.
• ATP is both consumed and produced within the pathway.
• NAD+ is reduced to NADH during the glyceraldehyde-3-phosphate dehydrogenase step.

Concept / Approach: Track electron flow: in glycolysis, NAD+ is reduced to NADH (it gains electrons). NADH may later be reoxidized to NAD+ via mitochondrial electron transport (aerobically) or by fermentation pathways (anaerobically). Glycolysis itself does not oxidize NADH; it generates it.

Step-by-Step Solution: Confirm ATP generation by substrate-level phosphorylation at the phosphoglycerate kinase and pyruvate kinase steps. Confirm oxygen independence: no O2 is needed for the core ten reactions. Identify the false statement: “oxidizes NADH to NAD+.” In reality, glycolysis reduces NAD+ to NADH. Recognize that two ATP are invested (hexokinase and phosphofructokinase steps).

Verification / Alternative check: Stoichiometry per glucose: invest 2 ATP; produce 4 ATP; net 2 ATP; produce 2 NADH; form 2 pyruvate.

Why Other Options Are Wrong: Option a, b, d, and e are correct statements; e is valid because glycolysis functions in cells lacking mitochondria (for example, erythrocytes).

Common Pitfalls: Confusing the role of fermentation (which reoxidizes NADH) with steps inside glycolysis.

Final Answer: The pathway oxidizes two moles of NADH to NAD+ per mole of glucose.